Initially, there was anticipation that mutations in p63 might contribute to the development of cancers in which p53 is not mutated; however, rather than mutation, overexpression of p63 and especially the ΔNp63 isoforms has been associated with malignant conditions including squamous carcinomas, such as those of the head and neck and skin [24,25,26]. This evidence concerns the gene TP53 and cancer.